Temperature Dependence of Magnetization Damping in Heusler Alloy Films

The Gilbert damping for $Co_2CrAl (Co_2Cr_{0.3}Fe_{0.7}Al)$ and $Ni_2MnSn$ Heusler alloy films was investigated as a function of temperature. The best films reveals the Gilbert damping nearly independent of temperature. Magnetic relaxation in $Co_2CrAl$ is strongly influenced by magnetic inhomogeneities due to phase separation. The best $Ni_2MnSn$ epitaxial films have comparable Gilbert damping α of 6× $10^{-3}$ as half-metallic $Co_2Cr_{0.3}Fe_{0.7}Al$ films with α = 3 × $10^{-3}$

Flammable properties of trichloroethylene

W artykule dokonano oceny własności palnych i wybuchowych trichloroetylenu według różnych źródeł literaturowych i unormowań prawnych. Wykonano pomiary temperatury zapłonu w tyglu zamkniętym według obowiązującej normy PN-EN 22719 (2000). Stwierdzono doświadczalnie, że TRI nie zapala się w warunkach opisanych w normie. Przeprowadzane badania i analiza wskazują na nieprawidłowość klasyfikowania urządzeń i osprzętu elektrycznego stosowanego w obecności TRI do grupy IIA.Estimation of flammable properties of trichlorethylene according to different literature sources has been given. Measurements of the ignition temperature in a closed cup under the obligatory standard PN-EN 22719 (2000) have been carried out. It has been experimentally proved that TRI does not ignite in conditions described in the obligatory standard. Experimental results and analysis have shown it is not correct to include in group IIA electrical devices and equipment used in the presence of trichlorethylene

Determination of Exchange and Rotatable Anisotropies in Co₂FeSi/IrMn Exchange Coupled Structures using Broadband Ferromagnetic Resonance

We determined exchange $H_{ex}$ and rotatable $H_{rot}$ anisotropy fields of multilayers that comprise 10 nm Co₂FeSi (CFS) layers exchange coupled to 20 nm IrMn layers by using ferromagnetic resonance with a vector network analyzer (VNA-FMR). The multilayer structures consist of IrMn/bottom (b)-CFS/IrMn/middle (m)-CFS/IrMn/top (t)-CFS/IrMn layers so that each CFS layer is surrounded by a pair of IrMn layers. In the structures, the exchange bias field propagates in such a way that $H_{ex}^{t}$ > $H_{ex}^{m}$ > $H_{ex}^{b}$ for the top, middle, and bottom layer, respectively. FMR response measured along the exchange bias (EB) axis consist of only two absorptions related to the (b+m)- and (t)-CFS layers, respectively. Exchange and rotatable anisotropy determined independently from angular and dispersion measurements of the resonance fields are nearly the same. Rotatable anisotropy field scales with the exchange bias field in these complex structures

Investigation of spin wave dynamics in Au/CoFeB/Au multilayers with perpendicular magnetic anisotropy

Abstract We have carried out an experimental investigation of the spin-wave dynamics in the Au/CoFeB/Au multilayer consisting of a ferromagnetic film with thicknesses of 0.8, 0.9 and 1.0 nm. We employed the Brillouin light scattering spectroscopy to measure the frequency of the spin waves in dependence on the wave vector. Additionally, we characterized the samples by ferromagnetic resonance measurements. We found that the considered samples exhibit perpendicular magnetic anisotropy with low damping, indicating small pumping effects. Furthermore, we found a nonreciprocal dispersion relation pointing at a non-negligible Dzyaloshinskii–Moriya interaction. These results make the Au/CoFeB/Au multilayer a compelling subject for further analysis and as a potential material for future applications within magnonics

Reprogrammability and Scalability of Magnonic Fibonacci Quasicrystals

Magnonic quasicrystals can be used to manipulate spin waves, offering possibilities beyond those of periodic magnonic crystals. The authors investigate one-dimensional magnonic Fibonacci quasicrystals and demonstrate the existence of collective spin waves over a broad range of wave vectors. The spin-wave spectra here are tunable by changing magnetic field amplitude (for continuous band-structure adjustment), magnetization configuration (for reprogrammability), or the dimensions of the elements (for scalability). Beyond being fundamentally interesting, these properties show that magnonic quasicrystals are promising for tomorrow's spintronic, microwave, and magnonic technologies